This invention relates generally to forms for use in the laying of concrete pads, and, more particularly, to curb stakes for use in holding the forms in place when the concrete pads are formed.
Curb stakes of this particular kind typically take the form of elongated shafts of wood or steel. The lower ends of the stakes are pointed, to facilitate their being driven into the ground immediately adjacent to a concrete form. The concrete forms are typically constructed of lengths of 2.times.4 or 2.times.6 lumber, which are laid end to end and held in place by a number of stakes spaced generally about two to six feet apart from each other. The stakes function to prevent the form from being displaced outwardly when the concrete is poured on the form's opposite or inward side.
The outward force of the concrete, and thus the concrete form, against the curb stakes has a tendency to cause the stakes to pivot outwardly, permitting the form to pivot along with them. If unchecked, this pivoting can result in the formation of a concrete pad having an undercut sidewall susceptible to chipping. Sometimes, this pivoting can even completely prevent the pouring of the pad.
In the past, this outward pivoting problem has frequently been prevented simply by using very long stakes, which can be driven a substantial distance into the ground. This is usually effective at preventing this outward pivoting. Since the stakes must be driven a substantial distance into the ground, however, additional labor costs are incurred in both driving the stakes into the ground and subsequently extracting them.
An alternative technique for preventing the outward pivoting of t4he concrete forms has been to use additional curb stakes, oriented at an angle with respect to the plane of the form, as shown in FIGS. 1 and 2. This solution is generally satisfactory, but requires the use of additional stakes, and, consequently, increased labor costs.
When finishing the surface of the concrete pad poured on the inward side of the concrete form, it is usually desirable to use a height adjustment and smoothing tool, such as a screed. Ideally, this tool is dragged along the top of the form, to smooth the concrete pad to a corresponding level. It is therefore important that the curb stakes be driven into the ground to a depth sufficient to bring their top surfaces to a level below that of the form. Driving the stakes to this depth can sometimes be difficult, especially when the stakes are relatively thin, as, for example, when they are formed from steel bar stock.
It should therefore be appreciated that there is a significant need for an improved curb stake that can resist both outward displacement and outward pivoting of a concrete form. Ideally, the curb stake should be configured so that it can be easily driven into the ground and subsequently extracted from it, and such that it can be readily driven into the ground to a level below the top surface of the form. The present invention fulfills this need.